Used by the Navy during WWII, the Drift Sight was a bombsight used as a simple mechanical device to measure the wind speed from the air and used that measurement to calculate the winds effects on the trajectory of the bombs. The Drift Sight eliminated the need for a stopwatch to perform this calculation. It is made of brass, steel and aluminum.
It was used in various Bomber and Reconnaissance aircraft such as the B-24, B-25, PBY Catalina and more. This model has a long extender that is attached to the sight.
It has an "astigmatizer" lever on the side and makers mark on a plate with details.
Measurements; 36" long and 8 1/2" wide.